part5.s~

/* Program that finds the largest number in a list of integers	    */

.equ LIST, 0x500		  /* Starting address of the list		    */
.equ ASCII1, 0x32
.equ ASCII2, 0x34
.equ ASCII3, 0x36
.equ ASCII4, 0x38
.equ ASCII5, 0x31
.equ ASCII6, 0x33
.equ ASCII7, 0x35
.equ ASCII8, 0x37

.equ BCD_MASK, 0x0F

.equ BCD_PACKED, 0x1000

.global _start
_start:
  
  movia r4, ASCII8
  and r4, r4, BCD_MASK

  slli r4, r4, 4  

  movia r5, ASCII7
  and r5, r5, BCD_MASK
  or r4, r4, r5

  slli r4, r4, 4

  movia r5, ASCII6
  and r5, r5, BCD_MASK
  or r4, r4, r5

  slli r4, r4, 4  

  movia r5, ASCII5
  and r5, r5, BCD_MASK
  or r4, r4, r5

  slli r4, r4, 4  

  movia r5, ASCII4
  and r5, r5, BCD_MASK
  or r4, r4, r5

  slli r4, r4, 4  

  movia r5, ASCII3
  and r5, r5, BCD_MASK
  or r4, r4, r5

  slli r4, r4, 4  

  movia r5, ASCII2
  and r5, r5, BCD_MASK
  or r4, r4, r5

  slli r4, r4, 4  

  movia r5, ASCII1
  and r5, r5, BCD_MASK
  or r4, r4, r5




	movia	r4, LIST	  /* r4 points to the start of the list	    */
	ldw	r5, 4(r4)	  /* r5 is a counter, initialize it with n    */
	addi	r6, r4, 8	  /* r6 points to the first number		    */
 	ldw	r7, (r6)	  /* r7 holds the largest number found so far */
		
LOOP:
	subi	r5, r5, 1	  /* Decrement the counter 			    */
	beq	r5, r0, DONE  /* Finished if r5 is equal to 0		    */
	addi	r6, r6, 4	  /* Increment the list pointer		    */
	ldw	r8, (r6)	  /* Get the next number			    */
	bge	r7, r8, LOOP  /* Check if larger number found		    */
	add	r7, r8, r0	  /* Update the largest number found	    */
	br	LOOP
DONE:
	stw	r7, (r4)	  /* Store the largest number into RESULT	    */

STOP:	
	br	STOP		  /* Remain here if done			    */

.org	0x500

.end